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arXiv · 2001.07767

Pseudospectra of the damped wave equation with unbounded damping

Ahmet Arifoski·Petr Siegl
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Abstract

We analyze pseudospectra of the generator of the damped wave equation with unbounded damping. We show that the resolvent norm diverges as $\Re z \to - \infty$. The highly non-normal character of the operator is a robust effect preserved even when a strong potential is added. Consequently, spectral instabilities and other related pseudospectral effects are present.

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BibTeXRIS

Ahmet Arifoski, Petr Siegl. 2020-01-21. Pseudospectra of the damped wave equation with unbounded damping. https://doi.org/10.1137/18m122140

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